Every once and a while after I visit a website (such as MLB.com and
NASDAQ.com) when I go back to it old information comes up on the
website. For instance, I went to MLB.com a week ago and now every time
I go the scores, news stories, stats, etc. will all be from that day a
week ago. Certain pieces of info on the website are current and
sometimes clicking a link will bring up current info, but most is old.
I clear the browser, delete history, cookies, etc. but no luck. The
only thing that solves the problem is running defrag, but only
temporarily, as soon the issue will reoccur. It only seems to happen on
one of my 3 computers. Any ideas?
What you’re experiencing isn’t all that uncommon, though its
persistence through the steps you’ve taken to clear it up is. The fact
that defragging has an impact is completely mysterious.
Let’s look at what happens under the hood, what steps we would
normally take to clear it up, and then make some guesses as to what
else you might try.
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As we’ve discussed before, your internet browser – be it Internet Explorer, Firefox, Opera or any of the others – typically keeps what’s called a ‘cache’ of recently downloaded files. The classic example is the image that is the logo at the top of every page of Ask Leo!. Your browser will download it once and then keep it in the cache so that on each page that uses the exact same logo the browser doesn’t need to download it again, it can simply use what’s in the cache.
Now if I change the logo, say I update it with a new one, then the browser is supposed to notice that the image is newer than what it has, and update/replace the copy in its cache. That way even for information that changes you always see the most current.
The problem you’re experiencing happens when the cache goes “wonky”. (Gotta love those not-so-technical terms.) In essence, that check for “is there something newer than what I have in my cache” fails, or the attempt to download and replace what’s in the cache fails.
Then you’ll see what you’re seeing: old information. In your case, it’s particularly noticeable since you’re expecting the information to change, and in fact know that it has, and yet the web page doesn’t update.
The top two solutions are actually pretty simple:
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F5/Refresh: about half the time simply refreshing the page will resolve the problem. The F5 key, or refresh, tells the browser to reload the entire page, which causes it to once again check the items in the cache for any updates. (It’s possible that it also ignores the cache, and simply re-downloads anyway.)
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Clear the Cache: about 90% of the remaining instances can be resolved simply by clearing the cache. Depending on your browser, clearing the cache often does more than simply deleting the files. Most caches have some sort of indexing system to speed up access to the files within it. Occasionally, it’s not the files that are at fault, but the index itself that has become corrupt. Clearing the cache also resets this index as well.
When those don’t work things definitely get more mystifying.
I’ll throw out a few ideas, in no particular order.
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Malware: certainly a possibility, as malware – particularly malware that targets your browser – can have all sorts of odd side effects.
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Anti-malware: as silly as it sounds, occasionally the very tools we use to protect us from malware can occasionally have unintended side effects, and this could be one of them. Consider turning off any browser-specific options in your anti-spyware or anti-virus software to see if things change. (Particularly if this system uses different tools than the ones that appear to work properly.)
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Filesystem corruption: I mentioned above that defrag having an impact is really odd, but it does lead me to this suggestion: run chkdsk. It’s possible that there’s a problem with the storage of files on disk that’s preventing the cache from working properly. In most cases, you’re probably running a single “C:” drive, so you’ll need to schedule the chkdsk for the next reboot. In a Windows Command Prompt, enter “chkdsk /f”:
C:\Documents and Settings\LeoN>chkdsk /f
The type of the file system is NTFS.
Cannot lock current drive. Chkdsk cannot run because the volume is in use by another
process. Would you like to schedule this volume to be
checked the next time the system restarts? (Y/N)And then respond “Y” to schedule the chkdsk.
For the record, things like cookies, history and the like should have no impact in the symptoms you’re experiencing. This is all about the browser’s cache, and its working properly, or improperly.
This is most likely not the problem since it only happens on one of three PCs. However, what if that PC is at work or using another ISP and behind behind a proxy. It doesn’t explain why defrag would work but does move the problem outside the PC.
You’re not doing the refresh properly. Hold down the Shift key, and then click the page reload button (FF and IE). That will do a force-refresh of all page content.
On an aside, “CTRL + F5” will tell the browser (at the least Firefox and IE) to re-download the current page entirely from the internet without using the cache.
This provides a way to fix some webpage issues without needing to completely clear and thus loose all your other information stored in the cache.
On a (sort of) related issues, I had put javascript code on a website I did, that used the “page last modified” data provided by the browser to show when the most recent changes were made. The problem was that it always showed the current date, even though I did not change anything on the page. It finally sank in that I was using “include” files on the site, and every time one of those was brought in the page was “updated”.
Sort of stupid of me, I guess. Anyway, now I always hard-code the date when making changes.
Jim S.
Could it be that there is an additional cache between the website and the browser? I remember making some changes on a website and publishing it, and no matter what I did, I could not view the updated pages in my browser. (I was halfway round the world from home.) However, when I logged in remotely to my home machine and visited the website, the updates were all there. Then back to the local machine and updates were not there. This led me to believe that the ISP in the other country might have been caching the webpages, and updating it only on their own refresh schedule.
10-Jun-2009
Could also be to do with the IE setting “Check for newer versions of stored pages”under Settings. The options are: Every visit to the page, Every time you start IE, Automatically, Never. The nearer the top of the list of options your settings are, the more likely the page is to update quickly.
As esourece notes, for IE the problem is that the default is “Automatically”, which is far from the same of the much safer “Every time”. “Automatically” seems to mean something like this “the longer it has been since a change was seen, the less often the server should be asked for the current copy”. Bottom line: On IE the only safe setting is “Every Time”!
My problem is slightly different. I think some of my customers do not realise that the page they see when they visit my website is an OLD version of the page without up-to-date information (prices, dates, etc.). Is there any way I can prevent their browsers from caching old versions of my site so that when they visit me again the information they get is definitely up to date?